JEE Mains · Physics · STD 12 - Nuclei
- JEE Mains 2021
- Hard
- MCQ
Consider the following statements : \(A.\) Atoms of each element emit characterstics spectrum. \(B.\) According to Bohr's Postulate, an electron in a hydrogen atom, revolves in a certain stationary orbit. \(C.\) The density of nuclear matter depends on the size of the nucleus. \(D.\) A free neutron is stable but a free proton decay is possible. \(E.\) Radioactivity is an indication of the instability of nuclei. Choose the correct answer from the options given below
Pick an option to check your answer.
Answer & Solution
Correct Answer
(A) \(A,B\) and \(E\) only
Step-by-step Solution
Detailed explanation
\((A)\) True, atom of each element emits characteristic spectrum.
\((B)\) True, according to Bohr's postulates \(m v r=\frac{n h}{2 \pi}\) and hence electron resides into orbits of specific radius called stationary orbits.
\((C)\) False, Density of nucleus is constant
\((D)\) False, \(A\) free neutron is unstable decays into proton and electron and antineutrino.
\((E)\) True unstable uncleus show radioactivity.
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